Enable Remote Desktop Logging (mstsc)

Go to “Start -> Run” and type ‘gpedit.msc‘ (without the quotes). Navigate to “Local Computer Policy -> Computer Configuration -> Windows Settings -> Security Settings -> Local Policies -> Audit Policies -> Audit logon events”. Highlight and right-click and select properties. Configure as desired.

Look in the Event Log (Security) for a Logon/Logoff Event 528. It should have a Logon Type 10.